Method for making a plastic-jacketed hair clip



I United States Patent [11] 3,540,491

[72] Inventor Nathan L. Solomon [56] References Cited P.0- B x 55 Englewood. New J y UNITED STATES PATENTS 67631 767,112 8/1904 Koehl 132/50 [211 1,988,822 1/1935 Weissenborn... 140/87 [22] Filed March 2,1966

17 1970 2,791,226 5/1957 KUIZ 132/50 [451 Paemed 3,230,127 1/1966 Cleereman etal 118 405 Primary ExaminerLouis G. Mancene Assistant Examiner-Gregory E. McNeil Attorney-Howard C. Miskin 54] METHOD FOR MAKING A PLASTIC-JACKETED g g: i ABSTRACT: A flexible hair clip made of metal with a thin, raw ng continuous, uniform jacket of tough, rigid plastic bonded to 50 Field ofSearch the metal. The plastic jacket is extruded about the metal prior to the forming and cutting operations. The formed, jacketed hair clip is heated to temper the metal without harming the plastic jacket.

Patented Nov. 17, 1970 INVENTOR. NATHAN L. SOLOMON Q Q m ME llh ATTORNEY METHOD FOR MAKING A PLASTlC-JACKETED HAIR CLIP This invention relates to a hair clip or clasp for the hair, and more particularly relates to a bobbypin or clasp for the hair having a uniform thin plastic jacket completely encasing a metal strand and a method of encasing and hermetically sealing in plastic an elongated wire or similar strand of any crossscctional contour and to shape it and temper it into a hair clip, such as a bobbypin without damaging or marring the plastic jacket.

It is common practice to form bobbypins from a metal strand or wire by crimping or corrugating the wire, trimming the wire to form workpieces, shaping the wire about a forming tool and then coating the formed wire pieces with paint, enamel or lacquer, such as by spraying or the like. A recognized disadvantage of these methods is that these coatings are not flexibleor durable and chip easily during the flexing while using, and further do not. completely cover the metal. In painting or spraying the formed article, there is a bare spot of metal normally on the inside of the bent portion of the bobbypin or hairpin, which is the contact point of a bar or arm, which keeps the bobbypin open while the paint, enamel or lacquer is applied by spraying or coating. The wave-setting solutions widely used to form curls today are often corrosive to the metals used in the hair accessory items. Similarly, the cosmetic material and hair dye used in various sprays and treating solutions for the hair often adversely react with the metal of these hair clips causing discoloration of the metal and the hair.

Also, during use the constant flexing and spreading of the arms'of the bobbypin or other hairpin loosen the paint or enamel from the metal core and cause flaking of the covering material, thereby exposing additional metal to the corrosive action of the various hair sprays and hair-waving lotions. Enamel is often worn away where the arms of the bobbypin come in contact when not in use. The flaking of the paint or lacquer and the powder from the wearing off of the enamel left on the hair detracts from the appearance of the user and results in bobbypins having a short life span.

Molded plastic hairpins have been used with limited success. While these all-plastic hair devices overcome many of the problems discussed above, they lacked springiness, flexibility and durability. To provide adequate strength, the molded plastic hair devices were made thicker and bulkier than the equivalent metal structure.

Attempts at coating metal bobbypins with plastic have not been satisfactory, since the plastic coating did not adhere to the metal sufficiently to remain bonded during the forming operations. The rigid plastic materials could not be applied to the hair items after forming, because of the corrugations and serpentine shape of, most of the finished pieces. The plastic coating on the metal became marred during the forming operation, so as to detract from the appearance and snag hair. Further, variations in the thickness of the plastic resulted in uneven tempering which made the metal too brittle or too soft.

Therefore, it is an object of the present invention to provide a simple and effective resilient clasp for the hair, such as a bobbypin, which is completely encased and hermetically sealed in plastic, so that the metal base will not rust or discolor regardless of the hair sprays and waving solutions used, and

which finish will not chip or flake off even after long use and severe flexing.

A further object of the present invention is to provide a resilient one-piece, formed strand ofwire completely jacketed with a tough plastic material, which will be long wearing and will not flake, chip or wear away during long use, always be attractive and will not snag the hair.

Another object of the present invention is to provide a method of uniformly jacketing with plastic an elongated wire or similar strand of material, having any cross-sectional contour, shaping the jacketed strand into a clasp for the hair, such as a bobbypin, and heat treating the jacketed clasp to give the clasp its desired resilient properties.

method of manufacturing a-hermetically sealed, resilient bob- I bypin having a permanently bonded thin plastic jucketwhich will not discolor or be adverselyaffected by the acids, hydroxides, chcmicals or dyes, such as used in hair-waving solutions and hair sprays.

Another object of the present invention is to provide a plastic jacketed bobbypin or the like for the hair that accomplishes all of the above and yet is inexpensive to fabricate, durable in use, pleasing to the eyes, reliable in operation, having permanent colors and a long life. I

Other objects and features of the invention will be apparent when the following description is considered in connection with the annexed drawings, in which:

FIG. I is a diagrammatic side elevational view of an apparatus suitable for carrying out the method of the invention;

FIG. 2 is a diagrammatic side elevational view of the apparatus for conveying the formed pins through various operations',

PK]. 3 is an enlarged front elevational view of a bobbypin. produced according to the invention; and

H6. 4 is a transverse cross-sectional view taken along line 4-4 of FIG. 3.

In accordance with the present invention, a thin uniform plastic jacket is applied to a wire strand. if the plastic jacket is too thick or is uneven in thickness, it will not form properly during the forming operations, or give a satisfactory appearance to the purchaser. During the crimping and bending operations a thick plastic layer will be marred by these forming operationsand form an uneven unattractive surface. Additionally, too thick of a jacket prevents good adhesion of the plastic to the metal strand, as well as being costly. Also, a thick coating results in uneven tempering of the wire by reason of the plastic coating reducing the heat transmitted to the metal through the plastic as the jacketed wire passes through a heating section.

As used herein, a'thin coating refers to a layer ofplastic on a side of a metal strand in the range of about .00l to .0055 inches. The layer must be uniform within the range of plus or minus .OOl of an inch. A jacketed strand that provides good results has a metal strip of about .022 inch thickness and the jacketed strand has an outside measurement of about .0275 inches.

Broadly stated, the new method comprises feeding an endless strand of filament through a cleaning station, passing the treated filament through an extrusion die, through which is continuously forced a plastic material, so that the plastic material is formed about the filament. The jacket is cooled and the jacketed filament is formed, cut to a predetermined length and bent into shape, its ends are coated and the formed wire is heated to a predetermined degree for tempering the metal strand. The finished product could be packaged or collected in any conventional manner.

The schematic diagram of FIG. 1 illustrates the general or rangement of the various mechanisms and apparatus for producing a wire form item coated with a uniform thin coating of plastic and formed into a hair clip ll illustrated in FIG. 3. As is shown, a continuous wireclement 10 is fed from a source of wire 12. Source 12 is shown as a payout reel rotatably mounted about a shaft 14. Wire 10 has any desired cross-sectional configuration. Advantageously, wire 10 is straightened 3 heating station 17 the cleaned wire is fed into an extruder 18 having a suitable die 20, shaped to provide the desired finished size of the arms of the hair pins. The inlet of extruder 18 into which wire the is "fed is coaxial with the extruder head l9, which contains the extruder orifice. A hard plastic material, such as nylon, is formed from the barrel of the extruder 18 under pressure through die orifice 20 longitudinally about wire at the outlet end of extruder head 19. In die orifice the plastic is formed about wire 10 as a covering or a jacket 24, having uniform outer dimensions. The outer dimensions of die orifice 20 are smaller than the outer dimensions of the coated wire. The speed of travel of wire 10 from die orifice 20 allows the coating 24 to enlarge in size a controlled amount after passing from die orifice 20, which provides a dimensionally constant-thickness of the coating.

As the coated filament 10 leaves die orifice 20, the hot plastic coating is cooled prior to further handling to avoid distortion or disturbing the coating. As shown, the hot plastic coating 24 is cooled by passing through a cooling station 26, which has cooling fluid therein, which would be either water or air. The plastic coated wire upon leaving cooling station 26 is safe to handle and be worked. As shown, the coated wire leaving cooling station 26 is driven or moved forward by a pair of driving wheels 28 rotating in the direction as shown. If desired, a capstan may also be used.

The plastic coated wire, indicated at 29, passes from driving wheels 28 into a forming operation. As shown, wire 29 is fed into a crimping'apparatus 30 for forming in the wire the proper corrugations, or multiple wave 31, shown in bobbypin ll in HO. 3. After a portion of the wire is properly corrugated. a cutoff tool trims the wire to a predetermined length and kicks up one end. Advantageously, the crimping, cutoff and kickup is formed in one operation, shown as mechanism 30. The formed wire forms, shown as 32, are fed from aparatus 30 into the final bending and forming unit 33 directly above a forming pin 34. Arranged beneath pin 34 is a carrier or band 35. Forming unit 33 bends wire form 32 about pin 34 and strips form 32 from pin 34 onto band 35, which conveys forms 32 onto the following operation. By varying the speed of band 35, the spacing of forms 32 thereon can be varied. The bending of form 32 is accomplished by a pair of arms 38 moving towards each other and forcing the ends of form 32 towards each other. Pin'34 aids in maintaining its corresponding wire form 32 against displacement. After the bending operation, arms v38 return to their initial position ready to receive their next workpiece. As indicated, the crimping, cutoff and bending operations result in a bobbypin 11, described above. This operation is continued to repeat the forming operations.

As the wire forms are formed into bobbypins, they are positioned on band and conveyed or carried through a dipping process, indicated-at 40, for coating or covering their exposed ends. The ends have metal exposed due to the trimming operation. The ends can be covered by spraying with a plastic, if desired. Advantagcously, the end-covering material is a plastisol, which is compatible with the plastic used for the coating, so as to form a complete plastic jacket. The jacketed bobbypins are then conveyed through a heater 42 where the coated ends are cured and the metal core is tempered to provide the resiliency and spring necessary for the bobbypin to operate properly. if the plastic coating on the bobbypin were not uniform, the metal strand would not have a uniform temper, so that portions with a thicker plastic coating would be less resilient than those portions of the metal having a thinner coating. However, if the steel is hardened too much by the coating being too thin, the metal would be too brittle and would snap in use, when expanded or stretched for inserting hair. Upon the hair clips leaving the heating station 42, the formed and jacketed hairpins are assembled in groups having a predetermined number of pins by mechanism 43, which bunches the pins in groups of 10, as shown. Mechanism 43 moves towards band 35 to hold the pins 11 thereon until a predetermined number are bunched, then moves away, so as to allow bunched pins 11 to move on. The band 35 continues its forward movement all ofthis time. These uniform groups of pins are conveyed to a carding operation, or packed in some manner, not shown.

Bobbypin 11 made in accordance with the present invention is shown in FIG. 3 having a pair of arms 48 and 50 with corrugations 31 along one arm 50, and being bent about portion 52. Arms 48 and 50 can be fle'xed many times with no harm to, or separation of, the coating 24 on the metal strand. The end of arm 50 has a kickup 54, which aids in receiving hair between arms 48 and 50. The free ends of arms 48 and 50 are coated, as at 56 and 58, respectively. I

Any plastic material for applying coating 24 may be used, which forms a tough, resilient, formable coating, and which has high resistance to deformation and chemicals, and has good properties of aging, light fastness and weathering. Some examples are .nylons, polycarbonates, fluorocarbons and acetal resins.

The speed of the forming and bending apparatus 30 and 33 is synchronized to the lineal speed of the coated filament l0 delivered from extruder 18 by feed wheels 28. The uniform spacing of the formed pin on hand 35 is controlled by the relative speeds of band 35 and the speed of pins leaving bending apparatus 33.

While a continuous coating and fabricating operation is shown in FIGS. 1 and 2, if desired, it can be done in several operations, namely taking up the coated wire on spools and retransferring the wire onto citherlarger or smaller spools for feeding through the forming and tempering operations. Also, the plastic when fed into the extruder can have various additional ingredients added for providing various colors and effccts.

Employing the method and apparatus of the present invention, provides a uniform thin coating ona metal strand, which falls within the range of about .00! to about .0055 inches on a side and controls closely the outer dimensions of the jacketed wire of any cross-sectional configuration. This thin coating can be mechanically formed, such as by corrugating and bentling, without breaking or separating the coating, or marring its smooth surface, and the metal strand then tempered within its jacket to provide the desired degree of springiness and flexibility. No metal is exposed to the chemicals used in hair sprays, or touches the scalp or hair of the user.

While preferred embodiments have been described, it would be understood that many variations thereof will be readily apparent to those skilled in the art without departing from the spirit thereof.

lclaim:

l. The method of making a plastic jacketed bobbypin which comprises cleaning a strip of metal, applying a tough rigid plastic continuously about said strip, passing said strip with said plastic through a die to form a thin, continuous, uniform plastic coat about said metal strip, cooling said plastic coating, crimping a portion of said coated metal strip to form multiple waves, trimming said strip to a predetermined length including said crimped portion, bending said length into a substantially U-shaped form having a pair of arms, coating the free end of each of said arms with a plastic material compatible with said first-mentioned plastic for hermetically sealing the entire metal strip, heating said formed strip at a temperature to temper the metal without decomposing said plastic jacket to provide springiness of the arms.

2. The method of making a bobbypin in accordance with claim 1, further including heating said strip of metal prior to applying said plastic about said strip.

3. The method of making a bobbypin in accordance with claim I, wherein said plastic material is a polyamide resin.

4. The method of making a bobbypin in accordance with claim 1, further including bending saidarms about a moving band frictionally engaging said arms with said band for carrying said pins from the forming operations.

5. The method of making a springy plastic-jacketed article which comprises cleaning a strip of metal, applying a tough ing said plastic jacket to provide springiness of the arms.

6. A method of making an article in accordance with claim 5, further including crimping a portion of said coated metal strip to form multiple waves therein.

7. A method of making an article in accordance with claim 5, wherein said plastic coating on said strip has a wall thickness of about .001 to about .0055 inches. 

